Only transmitters that are 'era-appropriate' are allowed to be used. More specifically, transmitters must employ tubes that were available in 1929 or earlier, and transmitters must be self-excited. No crystals allowed! Crystals were new and largely unaffordable for most hams back in the depression days.

1929 marked a real turning point in amateur radio as governments finally cracked-down on things such as frequency stability, out of band operations and re-alignment of call districts. In short, hams were henceforth required to behave themselves and to clean up their signals and methods of operation.

Although the new rules did a lot to improve things when it came to 'signal purity', there was still a long way to go ... but the wheels of improvement had been officially set in motion. The next decade would see monumental changes in both transmitter and receiver architecture, as engineers along with some particularly gifted amateurs, strove to unlock the challenges of this relatively new technology.

If you tune across the CW bands during the next two Saturday nights, you will have the rare opportunity to hear exactly what the bands must have sounded like back in the early '30s'.

For the most part you will hear single tube Hartley, Colpitts or TNT oscillators along with a few two-tube MOPAs thrown in. Many of them will suffer the same problems encountered by the boys of '29 ... chirp, drift, buzzy notes and frequency instability from antennas swaying in the wind.

This year, signals should be a little louder as well, since the previous power limitation of 10W input has been increased to 25W.

The MOPAs will sound much better but some surprisingly nice-sounding signals can be heard coming from properly tuned and optimised single-tube oscillators. I recall being blown away by the lovely sounding signal I heard from such a rig when first tuning into the BK activity several years ago, only to learn that it was a self-excited Hartley using 1/4" copper tubing for the oscillator tank circuit!

The '29 watering-hole on 80m will be around 3550-3580 kilocycles (be careful not to confuse this with kilohertz!) while the early afternoon to post-sunset 40m activity will be found from 7100-7125 kc. There may even be a few on the very low end of 160m. Although many of these transmitter styles were used on 20m and higher, BK rule-makers have wisely decided not to inflict these sounds on the present populace as it would likely keep the 'Official Observers' busy for several days writing pink-slips.

You can learn more about amateur radio happenings leading up to and following the 1929 crackdown in my earlier series of 'Why '29' blogs here:

Heck, there me even be time to throw something together for the following Saturday if you have a few parts and an older tube or two ... the '27 comes to mind and is readily found in many junk boxes. Maybe you know an old-timer or two with lots of parts that could help you out.

Let's hope for good conditions for this event as the last few years have been adversely affected by geomagnetic storming. Poor propagation or not, I guarantee there will be plenty of '29ers busy calling 'CQ AWA' on the low bands.